Chemical Investigations of the Sapindus mukorossi Seed Oil

Abstract

Two lipid fractions ‘A’ and ‘B’ were isolated from Sapindus mukorossi seed oil by preparative TLC. Fraction ‘A’ (70.4%, Rf value 0.76) is a normal triglyceride and its fatty acid compositions was determined by GLC. Fraction ‘B’ (29.6%, Rf value 0.51) shows the presence of nitrogenous constituents. It develops a reddish brown colour in contact with alkali or alkoxide solution. Percentages of individual acids present in fraction ‘A’ were found to be: palmitic, 5.5; stearic, 3.2; oleic, 64.6; linoleic, 2.9; arachidic, 3.1; eicosenoic, 20.1; minor acids, 0.6. Fraction ‘A’ is composed of 0.1,3.6,29.9 and 66.4 percent trisaturated, monounsaturated-disaturated, diunsaturated-monosaturated and triunsaturated glycerides respectively. On GLC analysis, the percentages of individual acids constituting fraction ‘B’ were found to be:palmitic, 3.8; stearic, 1.5; oleic, 33.6; linoleic, 2.9; arachidic, 11.1; eicosenoic, 30.2; behenic, 2.8; docosenoic, 1.4 and two unidentified acids 7.3 and 5.4. Fraction ‘B’ responded to hydrolysis by pancreatic lipase and the product with polarity equivalent to that of 2-mono-glyceride was isolated by TLC and converted to methyl ester. Percentages of individual acids constituting that methyl esters were found to be:palmitic, 11.8; stearic, 4.1; oleic, 12.8; linoleic, 3.7; arachidic, 8.3; eicosenoic, 10.2; behenic, 6.5; docosenoic, 4.2; and two unidentified acids 22.2 and 16.2. This non-glyceridic component of the S. mukorossi seed oil is a cyanolipid, 1-cyano-2-hydroxymethyl prop-1-ene-3-ol. The structure was confirmed by I. R., N.M.R. and Mass spectral-analysis.